Development of Quality Control Indexes of Feedstock for Cellulosic Bioethanol Production

Abstract

For producing cellulosic bioethanol stably, quality control indexes of feedstock are required. From the fact that Napiergrass can be harvested throughout the year in tropical region, growth was used as quality control indexes of feedstock. Each Napiergrass which grew 3-7 months at same field was carried out ammonia pretreatment and enzymatic saccharification under the same condition. Enzymatic saccharification efficiency decreased as Napiergrass grew. However, when Napiergrass samples which grew 5 months under various different conditions were compared, enzymatic saccharification efficiency and content of components were obviously different. Therefore, growth was not suitable for quality control indexes. Correlation coefficient between enzymatic saccharification efficiency and each component in Napiergrass was investigated. There was moderately strong correlation between enzymatic saccharification efficiency and lignin content (thioglycolic acid method , TGAL). From the above, TGAL was suitable for quality control indexes of feedstock for cellulosic bioethanol production. Furthermore, multiple linear regression analysis using saccharification efficiency as objective variable and contents of each component as explanatory variables, revealed that saccharification efficiency can be predicted from the contents of TGAL, glucose and crude protein with standard error of 3.50.